Field
Exemplary embodiments relate to touch sensing units. More particularly, exemplary embodiments relate to flexible touch sensing units and flexible display devices including the flexible touch sensing units.
Discussion of the Background
A touch sensing unit (e.g., a touch screen panel) is an input device that allows a user's instruction to be input by selecting an instruction link displayed on the screen of a display device or the like with a user's hand or an object. The touch sensing unit may be formed on a front surface of the display device and may convert the contact location into an electrical signal. Specifically, the user's hand or the object may directly contact the touch sensing unit at the contact location. Since such a touch sensing unit may replace separate input devices (such as a keyboard or mouse) connected to the display device, use of touch sensing units has been growing.
Touch sensing units may be divided into various types, including but not limited to a resistive overlay type, a photosensitive type, and a capacitive type. Among those touch sensing units, the capacitive touch sensing unit may convert a contact location into an electrical signal by sensing a change in capacitance between a conductive sensing pattern and an adjacent sensing pattern or a ground electrode when a user's hand or an object comes in contact with the touch sensing unit.
Recently, a flexible display device has been developed, so a touch sensing unit attached on the flexible display device must also be flexible.
A conventional flexible sensing unit may generally include sensing electrodes. However, damage such a crack may occur on the sensing electrodes when the flexible touch sensing unit is bent. In other words, when a conventional flexible display device is bent, the sensing electrodes of the flexible sensing unit, which have relatively low flexibility, may not endure the stress caused by the deformation of the sensing electrodes. Thus, a crack may occur on the sensing electrodes. A flexibility enhancing layer may be disposed on the flexible touch sensing unit to prevent cracking on the sensing electrodes, however, a thickness of the flexible display device may increase due to the addition of the flexibility enhancing layer.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the inventive concept, and, therefore, it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.